Merge pull request #152 from xushiwei/q

llgo/ssa: LoadPyModSyms; SetBlockEx AfterInit

.gitignore

@@ -18,6 +18,7 @@ _go/
 _runtime/
 _tinygo/
 build.dir/
+.vscode/
 
 # Test binary, built with `go test -c`
 *.test

chore/gentests/gentests.go

@@ -33,6 +33,7 @@ func main() {
 
 	llgenDir(dir + "/cl/_testlibc")
 	llgenDir(dir + "/cl/_testrt")
+	llgenDir(dir+"/cl/_testpy", "")
 	llgenDir(dir+"/cl/_testdata", "")
 }
 

cl/_testlibc/sqlite/out.ll

@@ -13,7 +13,7 @@ _llgo_0:
   br i1 %1, label %_llgo_1, label %_llgo_2
 
 _llgo_1:                                          ; preds = %_llgo_0
-  %2 = call ptr @sqlite3_errstr()
+  %2 = call ptr @sqlite3_errstr(i32 %0)
   %3 = call i32 (ptr, ...) @printf(ptr @0, i32 %0, ptr %2)
   call void @exit(i32 1)
   br label %_llgo_2
@@ -45,11 +45,11 @@ _llgo_0:
   %3 = extractvalue { ptr, i32 } %2, 0
   %4 = extractvalue { ptr, i32 } %2, 1
   call void @main.check(i32 %4)
-  %5 = call i32 @sqlite3_close()
+  %5 = call i32 @sqlite3_close(ptr %3)
   ret void
 }
 
-declare ptr @sqlite3_errstr()
+declare ptr @sqlite3_errstr(i32)
 
 declare i32 @printf(ptr, ...)
 
@@ -59,4 +59,4 @@ declare void @"github.com/goplus/llgo/internal/runtime.init"()
 
 declare { ptr, i32 } @"github.com/goplus/llgo/x/sqlite.OpenV2"(ptr, i32, ptr)
 
-declare i32 @sqlite3_close()
+declare i32 @sqlite3_close(ptr)

cl/_testpy/callpy/out.ll

@@ -8,6 +8,10 @@ source_filename = "main"
 @__llgo_py.os.getcwd = linkonce global ptr null
 @0 = private unnamed_addr constant [14 x i8] c"sqrt(2) = %f\0A\00", align 1
 @1 = private unnamed_addr constant [10 x i8] c"cwd = %s\0A\00", align 1
+@__llgo_py.math = external global ptr
+@2 = private unnamed_addr constant [5 x i8] c"sqrt\00", align 1
+@__llgo_py.os = external global ptr
+@3 = private unnamed_addr constant [7 x i8] c"getcwd\00", align 1
 
 define void @main.init() {
 _llgo_0:
@@ -18,6 +22,10 @@ _llgo_1:                                          ; preds = %_llgo_0
   store i1 true, ptr @"main.init$guard", align 1
   call void @"github.com/goplus/llgo/py/math.init"()
   call void @"github.com/goplus/llgo/py/os.init"()
+  %1 = load ptr, ptr @__llgo_py.math, align 8
+  call void (ptr, ...) @llgoLoadPyModSyms(ptr %1, ptr @2, ptr @__llgo_py.math.sqrt, ptr null)
+  %2 = load ptr, ptr @__llgo_py.os, align 8
+  call void (ptr, ...) @llgoLoadPyModSyms(ptr %2, ptr @3, ptr @__llgo_py.os.getcwd, ptr null)
   br label %_llgo_2
 
 _llgo_2:                                          ; preds = %_llgo_1, %_llgo_0
@@ -32,12 +40,14 @@ _llgo_0:
   call void @"github.com/goplus/llgo/internal/runtime.init"()
   call void @main.init()
   %2 = call ptr @PyFloat_FromDouble(double 2.000000e+00)
-  %3 = call ptr @PyObject_CallOneArg(ptr @__llgo_py.math.sqrt, ptr %2)
+  %3 = load ptr, ptr @__llgo_py.math.sqrt, align 8
-  %4 = call ptr @PyObject_CallNoArgs(ptr @__llgo_py.os.getcwd)
+  %4 = call ptr @PyObject_CallOneArg(ptr %3, ptr %2)
-  %5 = call double @PyFloat_AsDouble()
+  %5 = load ptr, ptr @__llgo_py.os.getcwd, align 8
-  %6 = call i32 (ptr, ...) @printf(ptr @0, double %5)
+  %6 = call ptr @PyObject_CallNoArgs(ptr %5)
-  %7 = call ptr @PyBytes_AsString()
+  %7 = call double @PyFloat_AsDouble(ptr %4)
-  %8 = call i32 (ptr, ...) @printf(ptr @1, ptr %7)
+  %8 = call i32 (ptr, ...) @printf(ptr @0, double %7)
+  %9 = call ptr @PyBytes_AsString(ptr %6)
+  %10 = call i32 (ptr, ...) @printf(ptr @1, ptr %9)
   ret void
 }
 
@@ -53,10 +63,12 @@ declare ptr @PyObject_CallOneArg(ptr, ptr)
 
 declare ptr @PyObject_CallNoArgs(ptr)
 
-declare double @PyFloat_AsDouble()
+declare double @PyFloat_AsDouble(ptr)
 
 declare i32 @printf(ptr, ...)
 
-declare ptr @PyBytes_AsString()
+declare ptr @PyBytes_AsString(ptr)
+
+declare void @llgoLoadPyModSyms(ptr, ...)
 
 declare void @Py_Initialize()

cl/_testpy/math/out.ll

@@ -5,6 +5,7 @@ source_filename = "math"
 @"math.init$guard" = global ptr null
 @__llgo_py.math = linkonce global ptr null
 @0 = private unnamed_addr constant [5 x i8] c"math\00", align 1
+@1 = private unnamed_addr constant [5 x i8] c"sqrt\00", align 1
 
 define void @math.init() {
 _llgo_0:
@@ -14,16 +15,20 @@ _llgo_0:
 _llgo_1:                                          ; preds = %_llgo_0
   store i1 true, ptr @"math.init$guard", align 1
   %1 = load ptr, ptr @__llgo_py.math, align 8
-  %2 = icmp ne ptr %1, null
+  call void (ptr, ...) @llgoLoadPyModSyms(ptr %1, ptr @1, ptr @__llgo_py.math.sqrt, ptr null)
-  br i1 %2, label %_llgo_2, label %_llgo_3
+  %2 = load ptr, ptr @__llgo_py.math, align 8
+  %3 = icmp ne ptr %2, null
+  br i1 %3, label %_llgo_2, label %_llgo_3
 
 _llgo_2:                                          ; preds = %_llgo_3, %_llgo_1, %_llgo_0
   ret void
 
 _llgo_3:                                          ; preds = %_llgo_1
-  %3 = call ptr @PyImport_ImportModule(ptr @0)
+  %4 = call ptr @PyImport_ImportModule(ptr @0)
-  store ptr %3, ptr @__llgo_py.math, align 8
+  store ptr %4, ptr @__llgo_py.math, align 8
   br label %_llgo_2
 }
 
 declare ptr @PyImport_ImportModule(ptr)
+
+declare void @llgoLoadPyModSyms(ptr, ...)

cl/compile.go

@@ -211,7 +211,7 @@ var (
 	argvTy = types.NewPointer(types.NewPointer(types.Typ[types.Int8]))
 )
 
-func (p *context) compileFuncDecl(pkg llssa.Package, f *ssa.Function, call bool) (llssa.Function, llssa.PyFunction, int) {
+func (p *context) compileFuncDecl(pkg llssa.Package, f *ssa.Function, call bool) (llssa.Function, llssa.PyObjRef, int) {
 	pkgTypes, name, ftype := p.funcName(f, true)
 	if ftype != goFunc {
 		if ftype == pyFunc {
@@ -250,7 +250,6 @@ func (p *context) compileFuncDecl(pkg llssa.Package, f *ssa.Function, call bool)
 	}
 	if nblk := len(f.Blocks); nblk > 0 {
 		fn.MakeBlocks(nblk) // to set fn.HasBody() = true
-		isPyMod := p.pyMod != ""
 		p.inits = append(p.inits, func() {
 			p.fn = fn
 			defer func() {
@@ -270,9 +269,9 @@ func (p *context) compileFuncDecl(pkg llssa.Package, f *ssa.Function, call bool)
 				off[i] = p.compilePhis(b, block)
 			}
 			for i, block := range f.Blocks {
-				doInit := (i == 0 && name == "main")
+				doMainInit := (i == 0 && name == "main")
-				doPyModInit := (isPyMod && i == 1 && f.Name() == "init" && sig.Recv() == nil)
+				doModInit := (i == 1 && f.Name() == "init" && sig.Recv() == nil)
-				p.compileBlock(b, block, off[i], doInit, doPyModInit)
+				p.compileBlock(b, block, off[i], doMainInit, doModInit)
 			}
 			for _, phi := range p.phis {
 				phi()
@@ -284,14 +283,14 @@ func (p *context) compileFuncDecl(pkg llssa.Package, f *ssa.Function, call bool)
 
 // funcOf returns a function by name and set ftype = goFunc, cFunc, etc.
 // or returns nil and set ftype = llgoCstr, llgoAlloca, llgoUnreachable, etc.
-func (p *context) funcOf(fn *ssa.Function) (aFn llssa.Function, pyFn llssa.PyFunction, ftype int) {
+func (p *context) funcOf(fn *ssa.Function) (aFn llssa.Function, pyFn llssa.PyObjRef, ftype int) {
 	pkgTypes, name, ftype := p.funcName(fn, false)
 	switch ftype {
 	case pyFunc:
 		if kind, mod := pkgKindByScope(pkgTypes.Scope()); kind == PkgPyModule {
 			pkg := p.pkg
 			fnName := pysymPrefix + mod + "." + name
-			if pyFn = pkg.PyFuncOf(fnName); pyFn == nil {
+			if pyFn = pkg.PyObjOf(fnName); pyFn == nil {
 				pyFn = pkg.NewPyFunc(fnName, fn.Signature, true)
 				return
 			}
@@ -329,41 +328,61 @@ func (p *context) funcOf(fn *ssa.Function) (aFn llssa.Function, pyFn llssa.PyFun
 	return
 }
 
-func (p *context) compileBlock(b llssa.Builder, block *ssa.BasicBlock, n int, doInit, pyModInit bool) llssa.BasicBlock {
+func modOf(name string) string {
+	if pos := strings.LastIndexByte(name, '.'); pos > 0 {
+		return name[:pos]
+	}
+	return ""
+}
+
+func (p *context) compileBlock(b llssa.Builder, block *ssa.BasicBlock, n int, doMainInit, doModInit bool) llssa.BasicBlock {
 	var last int
-	var instrs []ssa.Instruction
+	var pyModInit bool
+	var prog = p.prog
+	var pkg = p.pkg
+	var instrs = block.Instrs[n:]
 	var ret = p.fn.Block(block.Index)
 	b.SetBlock(ret)
-	if pyModInit {
+	if doModInit {
-		last = len(block.Instrs) - 1
+		if pyModInit = p.pyMod != ""; pyModInit {
-		instrs = block.Instrs[n:last]
+			last = len(instrs) - 1
-	} else {
+			instrs = instrs[:last]
-		instrs = block.Instrs[n:]
-		if doInit {
-			prog := p.prog
-			pkg := p.pkg
-			fn := p.fn
-			argc := pkg.NewVar("__llgo_argc", types.NewPointer(types.Typ[types.Int32]), llssa.InC)
-			argv := pkg.NewVar("__llgo_argv", types.NewPointer(argvTy), llssa.InC)
-			argc.Init(prog.Null(argc.Type))
-			argv.Init(prog.Null(argv.Type))
-			b.Store(argc.Expr, fn.Param(0))
-			b.Store(argv.Expr, fn.Param(1))
-			callRuntimeInit(b, pkg)
-			b.Call(pkg.FuncOf("main.init").Expr)
 		}
+		p.inits = append(p.inits, func() {
+			if objs := pkg.PyObjs(); len(objs) > 0 {
+				mods := make(map[string][]llssa.PyObjRef)
+				for name, obj := range objs {
+					modName := modOf(name)
+					mods[modName] = append(mods[modName], obj)
+				}
+				b.SetBlockEx(ret, llssa.AfterInit)
+				for modName, objs := range mods {
+					b.LoadPyModSyms(modName, objs...)
+				}
+			}
+		})
+	} else if doMainInit {
+		fn := p.fn
+		argc := pkg.NewVar("__llgo_argc", types.NewPointer(types.Typ[types.Int32]), llssa.InC)
+		argv := pkg.NewVar("__llgo_argv", types.NewPointer(argvTy), llssa.InC)
+		argc.Init(prog.Null(argc.Type))
+		argv.Init(prog.Null(argv.Type))
+		b.Store(argc.Expr, fn.Param(0))
+		b.Store(argv.Expr, fn.Param(1))
+		callRuntimeInit(b, pkg)
+		b.Call(pkg.FuncOf("main.init").Expr)
 	}
 	for _, instr := range instrs {
 		p.compileInstr(b, instr)
 	}
 	if pyModInit {
-		jump := block.Instrs[last].(*ssa.Jump)
+		jump := block.Instrs[n+last].(*ssa.Jump)
 		jumpTo := p.jumpTo(jump)
 		modPath := p.pyMod
 		modName := pysymPrefix + modPath
-		modPtr := p.pkg.NewPyModVar(modName).Expr
+		modPtr := pkg.NewPyModVar(modName, true).Expr
 		mod := b.Load(modPtr)
-		cond := b.BinOp(token.NEQ, mod, b.Prog.Null(mod.Type))
+		cond := b.BinOp(token.NEQ, mod, prog.Null(mod.Type))
 		newBlk := p.fn.MakeBlock()
 		b.If(cond, jumpTo, newBlk)
 		b.SetBlock(newBlk)
@@ -763,7 +782,7 @@ func (p *context) compileInstr(b llssa.Builder, instr ssa.Instruction) {
 	}
 }
 
-func (p *context) compileFunction(v *ssa.Function) (goFn llssa.Function, pyFn llssa.PyFunction, kind int) {
+func (p *context) compileFunction(v *ssa.Function) (goFn llssa.Function, pyFn llssa.PyObjRef, kind int) {
 	// v.Pkg == nil: means auto generated function?
 	if v.Pkg == p.goPkg || v.Pkg == nil {
 		// function in this package

py/_pyg/module.c

@@ -0,0 +1,25 @@
+#include <stdlib.h>
+#include <stdarg.h>
+
+// example:
+// llgoLoadPyModSyms(mod, "name1", &func1, "name2", &func2, NULL)
+
+typedef struct PyObject PyObject;
+
+PyObject* PyObject_GetAttrString(PyObject* mod, const char* attrName);
+
+void llgoLoadPyModSyms(PyObject* mod, ...) {
+    va_list ap;
+    va_start(ap, mod);
+    for (;;) {
+        const char* name = va_arg(ap, const char*);
+        if (name == NULL) {
+            break;
+        }
+        PyObject** pfunc = va_arg(ap, PyObject**);
+        if (*pfunc == NULL) {
+            *pfunc = PyObject_GetAttrString(mod, name);
+        }
+    }
+    va_end(ap);
+}

py/llgo.cfg

@@ -0,0 +1,6 @@
+{
+    "cl": [
+        "clang -emit-llvm -S -o module.ll -c _pyg/module.c",
+        "rm llgo_autogen.lla; zip llgo_autogen.lla llgo_autogen.ll module.ll",
+    ]
+}

py/module.go

@@ -50,4 +50,7 @@ func Import(name *Object) *Object
 // llgo:link (*Object).ModuleGetDict C.PyModule_GetDict
 func (m *Object) ModuleGetDict() *Object { return nil }
 
+// llgo:link (*Object).ModuleLoadSyms C.llgoLoadPyModSyms
+func (m *Object) ModuleLoadSyms(__llgo_va_list ...any) {}
+
 // -----------------------------------------------------------------------------

py/module.ll

@@ -0,0 +1,82 @@
+; ModuleID = '_pyg/module.c'
+source_filename = "_pyg/module.c"
+
+%struct.PyObject = type opaque
+
+; Function Attrs: noinline nounwind optnone ssp uwtable(sync)
+define void @llgoLoadPyModSyms(%struct.PyObject* noundef %0, ...) #0 {
+  %2 = alloca %struct.PyObject*, align 8
+  %3 = alloca i8*, align 8
+  %4 = alloca i8*, align 8
+  %5 = alloca i8*, align 8
+  %6 = alloca %struct.PyObject**, align 8
+  %7 = alloca %struct.PyObject**, align 8
+  store %struct.PyObject* %0, %struct.PyObject** %2, align 8
+  %8 = bitcast i8** %3 to i8*
+  call void @llvm.va_start(i8* %8)
+  br label %9
+
+9:                                                ; preds = %26, %1
+  %10 = va_arg i8** %3, i8*
+  store i8* %10, i8** %5, align 8
+  %11 = load i8*, i8** %5, align 8
+  store i8* %11, i8** %4, align 8
+  %12 = load i8*, i8** %4, align 8
+  %13 = icmp eq i8* %12, null
+  br i1 %13, label %14, label %15
+
+14:                                               ; preds = %9
+  br label %27
+
+15:                                               ; preds = %9
+  %16 = va_arg i8** %3, %struct.PyObject**
+  store %struct.PyObject** %16, %struct.PyObject*** %7, align 8
+  %17 = load %struct.PyObject**, %struct.PyObject*** %7, align 8
+  store %struct.PyObject** %17, %struct.PyObject*** %6, align 8
+  %18 = load %struct.PyObject**, %struct.PyObject*** %6, align 8
+  %19 = load %struct.PyObject*, %struct.PyObject** %18, align 8
+  %20 = icmp eq %struct.PyObject* %19, null
+  br i1 %20, label %21, label %26
+
+21:                                               ; preds = %15
+  %22 = load %struct.PyObject*, %struct.PyObject** %2, align 8
+  %23 = load i8*, i8** %4, align 8
+  %24 = call %struct.PyObject* @PyObject_GetAttrString(%struct.PyObject* noundef %22, i8* noundef %23)
+  %25 = load %struct.PyObject**, %struct.PyObject*** %6, align 8
+  store %struct.PyObject* %24, %struct.PyObject** %25, align 8
+  br label %26
+
+26:                                               ; preds = %21, %15
+  br label %9
+
+27:                                               ; preds = %14
+  %28 = bitcast i8** %3 to i8*
+  call void @llvm.va_end(i8* %28)
+  ret void
+}
+
+; Function Attrs: nocallback nofree nosync nounwind willreturn
+declare void @llvm.va_start(i8*) #1
+
+declare %struct.PyObject* @PyObject_GetAttrString(%struct.PyObject* noundef, i8* noundef) #2
+
+; Function Attrs: nocallback nofree nosync nounwind willreturn
+declare void @llvm.va_end(i8*) #1
+
+attributes #0 = { noinline nounwind optnone ssp uwtable(sync) "frame-pointer"="non-leaf" "min-legal-vector-width"="0" "no-trapping-math"="true" "probe-stack"="__chkstk_darwin" "stack-protector-buffer-size"="8" "target-cpu"="apple-m1" "target-features"="+aes,+crc,+crypto,+dotprod,+fp-armv8,+fp16fml,+fullfp16,+lse,+neon,+ras,+rcpc,+rdm,+sha2,+sha3,+sm4,+v8.5a,+zcm,+zcz" }
+attributes #1 = { nocallback nofree nosync nounwind willreturn }
+attributes #2 = { "frame-pointer"="non-leaf" "no-trapping-math"="true" "probe-stack"="__chkstk_darwin" "stack-protector-buffer-size"="8" "target-cpu"="apple-m1" "target-features"="+aes,+crc,+crypto,+dotprod,+fp-armv8,+fp16fml,+fullfp16,+lse,+neon,+ras,+rcpc,+rdm,+sha2,+sha3,+sm4,+v8.5a,+zcm,+zcz" }
+
+!llvm.module.flags = !{!0, !1, !2, !3, !4, !5, !6, !7, !8}
+!llvm.ident = !{!9}
+
+!0 = !{i32 2, !"SDK Version", [2 x i32] [i32 13, i32 3]}
+!1 = !{i32 1, !"wchar_size", i32 4}
+!2 = !{i32 8, !"branch-target-enforcement", i32 0}
+!3 = !{i32 8, !"sign-return-address", i32 0}
+!4 = !{i32 8, !"sign-return-address-all", i32 0}
+!5 = !{i32 8, !"sign-return-address-with-bkey", i32 0}
+!6 = !{i32 7, !"PIC Level", i32 2}
+!7 = !{i32 7, !"uwtable", i32 1}
+!8 = !{i32 7, !"frame-pointer", i32 1}
+!9 = !{!"Apple clang version 14.0.3 (clang-1403.0.22.14.1)"}

ssa/decl.go

@@ -285,36 +285,41 @@ func (p Function) Block(idx int) BasicBlock {
 
 // -----------------------------------------------------------------------------
 
-type aPyFunction struct {
+type aPyObjRef struct {
 	Expr
 	Obj Global
 }
 
-// PyFunction represents a python function.
+// PyObjRef represents a python object reference.
-type PyFunction = *aPyFunction
+type PyObjRef = *aPyObjRef
 
 // NewPyFunc creates a new python function.
-func (p Package) NewPyFunc(name string, sig *types.Signature, doInit bool) PyFunction {
+func (p Package) NewPyFunc(name string, sig *types.Signature, doInit bool) PyObjRef {
-	if v, ok := p.pyfns[name]; ok {
+	if v, ok := p.pyobjs[name]; ok {
 		return v
 	}
 	prog := p.Prog
-	prog.NeedPyInit = true
 	obj := p.NewVar(name, prog.PyObjectPtrPtr().RawType(), InC)
 	if doInit {
+		prog.NeedPyInit = true
 		obj.Init(prog.Null(obj.Type))
 		obj.impl.SetLinkage(llvm.LinkOnceAnyLinkage)
 	}
-	ty := &aType{obj.ll, rawType{sig}, vkPyFunc}
+	ty := &aType{obj.ll, rawType{types.NewPointer(sig)}, vkPyFuncRef}
 	expr := Expr{obj.impl, ty}
-	ret := &aPyFunction{expr, obj}
+	ret := &aPyObjRef{expr, obj}
-	p.pyfns[name] = ret
+	p.pyobjs[name] = ret
 	return ret
 }
 
-// PyFuncOf returns a function by name.
+// PyObjOf returns a python object by name.
-func (p Package) PyFuncOf(name string) PyFunction {
+func (p Package) PyObjOf(name string) PyObjRef {
-	return p.pyfns[name]
+	return p.pyobjs[name]
+}
+
+// PyObjs returns all used python objects in this project.
+func (p Package) PyObjs() map[string]PyObjRef {
+	return p.pyobjs
 }
 
 // -----------------------------------------------------------------------------

ssa/expr.go

@@ -1238,7 +1238,7 @@ func (b Builder) Call(fn Expr, args ...Expr) (ret Expr) {
 		log.Println(b.String())
 	}
 	var kind = fn.kind
-	if kind == vkPyFunc {
+	if kind == vkPyFuncRef {
 		return b.pyCall(fn, args)
 	}
 	var ll llvm.Type

ssa/package.go

@@ -140,6 +140,7 @@ type aProgram struct {
 	pyImpTy    *types.Signature
 	callNoArgs *types.Signature
 	callOneArg *types.Signature
+	loadPyModS *types.Signature
 
 	NeedRuntime bool
 	NeedPyInit  bool
@@ -257,12 +258,12 @@ func (p Program) NewPackage(name, pkgPath string) Package {
 	gbls := make(map[string]Global)
 	fns := make(map[string]Function)
 	stubs := make(map[string]Function)
-	pyfns := make(map[string]PyFunction)
+	pyobjs := make(map[string]PyObjRef)
 	pymods := make(map[string]Global)
 	p.NeedRuntime = false
 	// Don't need reset p.needPyInit here
 	// p.needPyInit = false
-	return &aPackage{mod, gbls, fns, stubs, pyfns, pymods, p}
+	return &aPackage{mod, gbls, fns, stubs, pyobjs, pymods, p}
 }
 
 // PyObjectPtrPtr returns the **py.Object type.
@@ -366,7 +367,7 @@ type aPackage struct {
 	vars   map[string]Global
 	fns    map[string]Function
 	stubs  map[string]Function
-	pyfns  map[string]PyFunction
+	pyobjs map[string]PyObjRef
 	pymods map[string]Global
 	Prog   Program
 }
@@ -506,6 +507,16 @@ func (p Program) tyCallOneArg() *types.Signature {
 	return p.callOneArg
 }
 
+func (p Program) tyLoadPyModSyms() *types.Signature {
+	if p.loadPyModS == nil {
+		objPtr := p.PyObjectPtr().raw.Type
+		paramObjPtr := types.NewParam(token.NoPos, nil, "mod", objPtr)
+		params := types.NewTuple(paramObjPtr, VArg())
+		p.loadPyModS = types.NewSignatureType(nil, nil, nil, params, nil, false)
+	}
+	return p.loadPyModS
+}
+
 // PyInit initializes Python for a main package.
 func (p Package) PyInit() bool {
 	if fn := p.FuncOf("main"); fn != nil {
@@ -518,15 +529,17 @@ func (p Package) PyInit() bool {
 }
 
 // NewPyModVar creates a new global variable for a Python module.
-func (p Package) NewPyModVar(name string) Global {
+func (p Package) NewPyModVar(name string, doInit bool) Global {
 	if v, ok := p.pymods[name]; ok {
 		return v
 	}
 	prog := p.Prog
 	objPtr := prog.PyObjectPtrPtr().raw.Type
 	g := p.NewVar(name, objPtr, InC)
-	g.Init(prog.Null(g.Type))
+	if doInit {
-	g.impl.SetLinkage(llvm.LinkOnceAnyLinkage)
+		g.Init(prog.Null(g.Type))
+		g.impl.SetLinkage(llvm.LinkOnceAnyLinkage)
+	}
 	p.pymods[name] = g
 	return g
 }
@@ -538,9 +551,30 @@ func (b Builder) ImportPyMod(path string) Expr {
 	return b.Call(fnImp, b.CStr(path))
 }
 
+// LoadPyModSyms loads python objects from specified module.
+func (b Builder) LoadPyModSyms(modName string, objs ...PyObjRef) Expr {
+	pkg := b.Func.Pkg
+	fnLoad := pkg.pyFunc("llgoLoadPyModSyms", b.Prog.tyLoadPyModSyms())
+	modPtr := pkg.NewPyModVar(modName, false).Expr
+	mod := b.Load(modPtr)
+	args := make([]Expr, 1, len(objs)*2+2)
+	args[0] = mod
+	nbase := len(modName) + 1
+	for _, o := range objs {
+		fullName := o.impl.Name()
+		name := fullName[nbase:]
+		args = append(args, b.CStr(name))
+		args = append(args, o.Expr)
+	}
+	prog := b.Prog
+	args = append(args, prog.Null(prog.CStr()))
+	return b.Call(fnLoad, args...)
+}
+
 func (b Builder) pyCall(fn Expr, args []Expr) (ret Expr) {
 	prog := b.Prog
 	pkg := b.Func.Pkg
+	fn = b.Load(fn)
 	sig := fn.raw.Type.(*types.Signature)
 	params := sig.Params()
 	n := params.Len()

ssa/ssa_test.go

@@ -147,8 +147,8 @@ func TestPyFunc(t *testing.T) {
 	if pkg.NewPyFunc("a", sig, false) != a {
 		t.Fatal("NewPyFunc(a) failed")
 	}
-	foo := pkg.NewPyModVar("foo")
+	foo := pkg.NewPyModVar("foo", false)
-	if pkg.NewPyModVar("foo") != foo {
+	if pkg.NewPyModVar("foo", false) != foo {
 		t.Fatal("NewPyModVar(foo) failed")
 	}
 }

ssa/stmt_builder.go

@@ -21,6 +21,7 @@ import (
 	"fmt"
 	"go/types"
 	"log"
+	"strings"
 
 	"github.com/goplus/llvm"
 )
@@ -76,6 +77,7 @@ type InsertPoint int
 const (
 	AtEnd InsertPoint = iota
 	AtStart
+	AfterInit
 )
 
 // SetBlockEx sets blk as current basic block and pos as its insert point.
@@ -88,12 +90,35 @@ func (b Builder) SetBlockEx(blk BasicBlock, pos InsertPoint) Builder {
 		b.impl.SetInsertPointAtEnd(blk.impl)
 	case AtStart:
 		b.impl.SetInsertPointBefore(blk.impl.FirstInstruction())
+	case AfterInit:
+		b.impl.SetInsertPointBefore(instrAfterInit(blk.impl))
 	default:
 		panic("SetBlockEx: invalid pos")
 	}
 	return b
 }
 
+func instrAfterInit(blk llvm.BasicBlock) llvm.Value {
+	instr := blk.FirstInstruction()
+	for {
+		instr = llvm.NextInstruction(instr)
+		if notInit(instr) {
+			return instr
+		}
+	}
+}
+
+func notInit(instr llvm.Value) bool {
+	switch op := instr.InstructionOpcode(); op {
+	case llvm.Call:
+		if n := instr.OperandsCount(); n == 1 {
+			fn := instr.Operand(0)
+			return !strings.HasSuffix(fn.Name(), ".init")
+		}
+	}
+	return true
+}
+
 // Panic emits a panic instruction.
 func (b Builder) Panic(v Expr) {
 	if debugInstr {

ssa/type.go

@@ -43,7 +43,7 @@ const (
 	vkFuncDecl
 	vkFuncPtr
 	vkClosure
-	vkPyFunc
+	vkPyFuncRef
 	vkTuple
 	vkPhisExpr = -1
 )

ssa/type_cvt.go

@@ -57,8 +57,11 @@ func (p Program) Type(typ types.Type, bg Background) Type {
 
 // FuncDecl converts a Go/C function declaration into raw type.
 func (p Program) FuncDecl(sig *types.Signature, bg Background) Type {
+	recv := sig.Recv()
 	if bg == InGo {
-		sig = p.gocvt.cvtFunc(sig, sig.Recv())
+		sig = p.gocvt.cvtFunc(sig, recv)
+	} else if recv != nil { // even in C, we need to add ctx for method
+		sig = FuncAddCtx(recv, sig)
 	}
 	return &aType{p.toLLVMFunc(sig), rawType{sig}, vkFuncDecl}
 }

x/sqlite/sqlite.ll

@@ -8,7 +8,7 @@ source_filename = "github.com/goplus/llgo/x/sqlite"
 define ptr @"(*github.com/goplus/llgo/x/sqlite.Errno).Errstr"(ptr %0) {
 _llgo_0:
   %1 = load i32, ptr %0, align 4
-  %2 = call ptr @sqlite3_errstr()
+  %2 = call ptr @sqlite3_errstr(i32 %1)
   ret ptr %2
 }
 
@@ -84,7 +84,7 @@ _llgo_2:                                          ; preds = %_llgo_1, %_llgo_0
   ret void
 }
 
-declare ptr @sqlite3_errstr()
+declare ptr @sqlite3_errstr(i32)
 
 declare ptr @"github.com/goplus/llgo/internal/runtime.AllocZ"(i64)
 
@@ -92,8 +92,8 @@ declare i32 @sqlite3_open(ptr, ptr)
 
 declare i32 @sqlite3_open_v2(ptr, ptr, i32, ptr)
 
-declare i32 @sqlite3_prepare(ptr, i32, ptr, ptr)
+declare i32 @sqlite3_prepare(ptr, ptr, i32, ptr, ptr)
 
-declare i32 @sqlite3_prepare_v2(ptr, i32, ptr, ptr)
+declare i32 @sqlite3_prepare_v2(ptr, ptr, i32, ptr, ptr)
 
-declare i32 @sqlite3_prepare_v3(ptr, i32, i32, ptr, ptr)
+declare i32 @sqlite3_prepare_v3(ptr, ptr, i32, i32, ptr, ptr)